What time of day should I work out? Here's what researchers say is optimal

Those bragging about working out well before the sun rises may want to rethink their schedule, as a new large cohort study of over 90,000 people has found that working out during the afternoon might provide the most benefits.

According to research published Feb. 18 in the journal Nature Communications,while moderate to intense physical activity, at any point of the day reduces the risk of cardiovascular disease and cancer mortality— timing a workout correctly could maximize its benefits.

Researchers in China and Sweden used data from the UK Biobank --a large biomedical database that contains health information from half-a-million U.K. residents --to examine the impact of physical activity in reducing mortality risk for certain illnesses and whether the timing of exercise was a factor.

The UK Biobank has seven-day activity data from over 100,000 people who wore accelerometers, devices that can record activity 24-hours a day. In total, data from about 92,000 people was used for the study.

The researchers also had access to intersecting data on the participants, including age, sex, income, smoking status and more, to draw their conclusions.

People were split into four groups based on when they exercised, and researchers checked records for up to seven years after participants joined the UK Biobank to assess movement and mortality.

Authors said in their report that the research is “the first evidence” that moderate to intense physical activity, regardless of the time of day, is associated with living longer, and a lower risk of death from cancer or cardiovascular disease.

Additionally, it showed the group that worked out fromthe midday to the afternoon --which researchers characterized as 11 a.m. to 5 p.m. --or spread out exercise through the day, had an even lower risk of dying from cardiovascular disease or other causes. However, the risk of dying from cancer was not lower for the afternoon workout group, compared to any other group.

SO WHEN SHOULD YOU WORK OUT?

The benefits from working out during the afternoon were more pronounced in older people, men, people who are less active and those with pre-existing cardiovascular diseases, the researchers state.

One reason for afternoon workouts appearing to be more beneficial is people are less likely to have a heart attack during that time period, they said.

Another factor has to do with behaviour, as research shows working out after a meal like lunch is “more effective” in controlling glucose levels, rather than walking in the morning before eating, according to the study.

Researchers emphasized working out at any time of day is beneficial, and their findings can be used to maximize benefits of exercise— especially for groups where timing is more important, such as older people.

The academics who authored the Nature Communications study also highlight past studies found working out in the morning might be better in reducing hyperglycemia.

But, they explain, these studies were done on animals like mice rather than humans, and prior to their study being published, the results of past research on humans and exercise timing was “inconclusive” and “contradictory,” as several different experimental studies had different outcomes